1. Technical Field
The present invention relates to a clamping structure for mounting a reducer and, more particularly, to a clamping structure for mounting a reducer of fire sprinklers, in which a clamp door can be easily rotated about a rotation coupling point of a hinge pin to be tightly secured to an opposite side of the rotation coupling point.
2. Description of the Related Art
Generally, as buildings become taller and larger, various fire suppression apparatuses have been developed and used to achieve effective and efficient suppression of fire in the event of a fire in the buildings.
As fire suppression apparatuses are generally used, sprinklers capable of suppressing fire by spraying high-pressure water from the ceiling of each floor of buildings are essentially provided to the buildings.
In order to mount a sprinkler in a building, a main water supply pipe for supplying water through the ceiling is provided to the building, and the sprinkler is coupled to a connection pipe which connects a plurality of branch water supply pipes to the main water supply pipe, such that water is intensively supplied to a place, at which fire occurs, in order to suppress the fire.
In one example, referring to FIG. 1, Korean Utility Model Registration No. 20-0179175 assigned to the present inventor discloses a fire suppression apparatus including a sprinkler, which is connected to a lower side of a reducer 10 by a typical flexible joint and sprays water onto a predetermined place, wherein the reducer 10 is formed at four lateral sides thereof with contact surfaces 12 to be inserted into a square insertion hole 32, and a plurality of wing bolts 38 is secured to a predetermined number of screw holes 36 formed on a lateral side of a reducer securing bracket 30 having an opening 34, into which a square bar 20 is inserted, and applies pressure to the contact surfaces 12 of the reducer 10 by applying pressure to the square bar 20. The reducer securing bracket 30 is formed at upper and lower sides thereof with through-holes 35 and is secured to a screw support withdrawn from the ceiling by upper and lower nuts.
The contact surfaces 12 of the reducer 10 are formed by cutting a round outer surface of the reducer 10, and the reducer 10 is formed at the lower side thereof with a sprinkler mounting portion 26 to which a sprinkler head is secured.
In another example, referring to FIG. 2, a clamp 300 disclosed in Korean Patent No. 10-1014385 based on the technique of FIG. 1 can be moved to a desired place, with a support frame (square bar) 100 inserted into one side of a clamp body 131, and a nut 138c serving to open or close a clamp door 134 is loosened, such that the clamp door 134 can be rotated about a hinge pin 133 to be opened. The clamp body 131 and the clamp door 134 are formed with a clamp groove 132 and a coupling groove 135, respectively, to define a space capable of receiving a body 222 of a sprinkler 200 when the body 222 is inserted into the clamp 300. Thus, in order to provide a clamping state between the clamp 300 and the sprinkler 200, the body 222 of the sprinkler 200 is inserted into the clamp door 134 in an opening/closing direction of the clamp door 134 without separating a spray nozzle 224 from the body 222, and, with the clamp door 134 closed, a bolt coupling rod 137c coupled to the clamp body 131 is inserted into a securing groove 136 of the clamp door 134, and then, a nut 138c is fitted to the bolt coupling rod 137c. 
However, as shown in FIG. 1, in the above example, since the square insertion hole 32 is formed in the reducer securing bracket 30 and the reducer 10 is inserted and secured thereto, the reducer 10 provides good tightness, but has a problem in that separation or disassembly is inconvenient.
Moreover, as shown in FIG. 2, in the other example, since the clamp 300 has the structure wherein the clamp door 134 is rotated about the rotation coupling point of the hinge pin 133 to allow the securing groove 136 of the clamp door 134 to be open at one side thereof such that the nut 138c is fitted to the bolt coupling rod 137c inserted into the securing groove 136, there are problems in that coupling is difficult and disassembly operation is inconvenient due to the need to rotate the nut 138c during disassembly. In addition, since the securing groove 136 of the clamp door 134 has the one side-open structure, when a strong torque of 900 Kg/m2 or more is applied to the clamp 300, the clamp body 131 and the clamp door 134 come apart or are distorted, thereby making it difficult to use the clamp 300.